Nova-Tech Pulsatron Series MP - Manual (Page 21)

21
The pump responds to a 4-20mA signal as follows when the high rate is 100%, the low rate is 0%, the high signal
is 20mA and the low signal is 4mA. (Figure O below shows straight response)
4-20 mA Signal
4
6
8
10
12
14
16
18
20
100% 75% 50% 25% 0%
Pump Speed
DC
m
A
Figure N
The pump responds to a 20-4mA signal as follows when the high rate is 0% the low rate is 100%, the high signal
is 20mA and the low signal is 4mA. However, the high signal can never be set below the low signal, and the low
signal cannot be set above the high signal setting. Only the stroke rate may be inverted. (Figure O below shows
straight response)
20-4 mA Signal
4
6
8
10
12
14
16
18
20
0% 25% 50% 75% 100
Pump Speed
DC
m
A
Figure O
The pump responds to a user defined scaled signal as follows when the high rate is 100% the low rate is 0%, the
high signal is 20mA and the low signal is 12mA. (Figure O-1 below shows an example of a possible user defined
scale)
Example of a Custom Scale
4
6
8
10
12
14
16
18
20
100% 50% 0%
Pump Speed
DC
m
A
Figure O - 1
The signal cord is provided with the pump and has the following polarity:
White = Positive (+)
Black = Common
Signal input impedance is 100 ohms.